This invention relates generally to inspection techniques, and more specifically to methods and apparatus for aligning components for inspection.
Accurately measuring a surface of a component may be a significant factor in determining a manufacturing time of the component, as well in determining subsequent maintenance and repair costs and activities. Specifically, when the component is a gas turbine engine blade, accurately measuring the contour of the blade may be one of the most significant factors affecting an overall cost of fabrication of the gas turbine engine, as well as subsequent modifications, repairs, and inspections of the blade. For example, at least some known gas turbine engine blades include a tip shroud that for performance reasons requires an accurately machined radius along the tip and center section of the blade. At least some known fabrication systems establish the radius using a system of datums referenced about the profile of the blade.
At least some known inspection processes use coordinate measuring machines (CMMs) to obtain dimensional information for a component. Within at least some CMMS, the component is held within a three-coordinate measurement space such that one or more datums are exposed to the CMM. A CMM probe is also positioned within the three-coordinate measurement space and contacts one or more of the datums, at which time a position of the probe tip is measured. The process must be repeated many times to determine a surface contour of the component, and as such, using a CMM may be time-intensive, and result in high cycle times and costs. Furthermore, it may be difficult to align the components in a position that facilitates accurate inspection of the component without distorting the profile and/or features of the component.